Performance Difference Between C and C++ Style File IO

Question

I\'ve always heard that C++ file I/O operations are much much slower then C style I/O. But I didn\'t find any practical references on comparatively how slow they actually ar

Answer 1

You're using endl to print a newline. That is the problem here, as it does more than just printing a newline — endl also flushes the buffer which is an expensive operation (if you do that in each iteration).

Use \n if you mean so:

file << i << '\n';

And also, must compile your code in release mode (i.e turn on the optimizations).